Alexis Maybank and Alexandra Wilkis Wilson created Gilt Groupe back in 2007 to sell high-end luxury goods from designers at up to 70% off retail prices during 36-hour "flash sales." The result? Booming revenues.

Gilt should more than double sales to between $400 and $500 million this year. It's also expanded with a men's editorial web site, Gilt MANual, offering lifestyle content and sartorial advice, a slick Chrome OS app that actually provides a better user experience than the standard site, and most recently, an agreement with Dwell magazine for the sales of 20 prefab homes and architectural designs going for $12,500, half what they would normally go for. As Susan Lyne, company chairman, told us back in September, expect mainstream forays with mass consumer companies like say, Starbucks, moire full-price retail items, and even an IPO some time down the line.